U.S. patent number 10,666,081 [Application Number 15/563,437] was granted by the patent office on 2020-05-26 for battery management system.
This patent grant is currently assigned to Hyperdrive Innovation Limited. The grantee listed for this patent is Hyperdrive Innovation Limited. Invention is credited to Stephen Irish, Robin Shaw.
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United States Patent |
10,666,081 |
Irish , et al. |
May 26, 2020 |
Battery management system
Abstract
A battery management system for use in charging a rechargeable
battery is disclosed. The battery management system comprises a
controller and a temperature sensor, wherein the temperature sensor
is configured to provide a temperature signal based on a
temperature of the rechargeable battery, and wherein the controller
is configured to control a charging current for charging the
rechargeable battery based on the temperature signal. In response
to the temperature signal indicating that the temperature exceeds a
first threshold temperature signal value the charging current is
tapered down as a function of increasing temperature.
Inventors: |
Irish; Stephen (Sunderland Tyne
and Wear, GB), Shaw; Robin (Sunderland Tyne and Wear,
GB) |
Applicant: |
Name |
City |
State |
Country |
Type |
Hyperdrive Innovation Limited |
Sunderland Tyne and Wear |
N/A |
GB |
|
|
Assignee: |
Hyperdrive Innovation Limited
(Sunderland, GB)
|
Family
ID: |
55359214 |
Appl.
No.: |
15/563,437 |
Filed: |
December 30, 2016 |
PCT
Filed: |
December 30, 2016 |
PCT No.: |
PCT/GB2016/054090 |
371(c)(1),(2),(4) Date: |
September 29, 2017 |
PCT
Pub. No.: |
WO2017/115091 |
PCT
Pub. Date: |
July 06, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20180316207 A1 |
Nov 1, 2018 |
|
Foreign Application Priority Data
|
|
|
|
|
Dec 30, 2015 [GB] |
|
|
1523105.3 |
Jun 22, 2016 [GB] |
|
|
1610936.5 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02J
7/0016 (20130101); H01M 10/425 (20130101); H01M
10/486 (20130101); H02J 7/007192 (20200101); H01M
10/443 (20130101); H01M 10/48 (20130101); H02J
7/0091 (20130101); H02J 7/0014 (20130101); H02J
7/0029 (20130101); H01M 2220/20 (20130101); H02J
7/00304 (20200101); H01M 2010/4271 (20130101) |
Current International
Class: |
H02J
7/00 (20060101); H01M 10/44 (20060101); H01M
10/42 (20060101); H01M 10/48 (20060101) |
Field of
Search: |
;320/104 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
103312010 |
|
Sep 2013 |
|
CN |
|
105162215 |
|
Dec 2015 |
|
CN |
|
1710889 |
|
Oct 2006 |
|
EP |
|
1848088 |
|
Oct 2007 |
|
EP |
|
2131470 |
|
Dec 2009 |
|
EP |
|
2584666 |
|
Apr 2013 |
|
EP |
|
2690744 |
|
Jan 2014 |
|
EP |
|
2787594 |
|
Oct 2014 |
|
EP |
|
2866294 |
|
Apr 2015 |
|
EP |
|
H09219901 |
|
Aug 1997 |
|
JP |
|
9310589 |
|
May 1993 |
|
WO |
|
9617397 |
|
Jun 1996 |
|
WO |
|
2011003513 |
|
Jan 2011 |
|
WO |
|
2012020306 |
|
Feb 2012 |
|
WO |
|
2012030455 |
|
Mar 2012 |
|
WO |
|
Other References
Examination Report for Application No. GB1523114.5, dated Jan. 16,
2018. cited by applicant .
Combined Search and Examination Report for GB Application No.
1523113.7 dated, Jun. 24, 2016. cited by applicant .
International Search Report and Written Opinion for
PCT/GB2016/054090, dated Apr. 26, 2017. cited by applicant .
Search Report for GB Application No. 1523111.1, dated Jan. 14,
2016. cited by applicant .
Combined Search and Examination Report for GB Application No.
1523114.5, dated Jun. 23, 2016. cited by applicant.
|
Primary Examiner: Tso; Edward
Assistant Examiner: Omar; Ahmed H
Claims
The invention claimed is:
1. A battery management system for use in charging a rechargeable
battery, the battery management system comprising a controller and
a temperature sensor, wherein: the temperature sensor is configured
to provide a temperature signal based on a temperature of the
rechargeable battery; and wherein the controller is configured to
control a charging current for charging the rechargeable battery
based on the temperature signal, so that in response to the
temperature signal indicating that the temperature exceeds a first
threshold temperature signal value the charging current is tapered
down as a function of increasing temperature; and balance cells of
the battery if the charging current supplied to the battery exceeds
a selected charging current threshold.
2. The battery management system of claim 1 wherein in response to
the temperature signal indicating that the temperature exceeds a
second threshold temperature, no charging current is supplied to
the battery.
3. The battery management system of claim 1 further comprising a
charge indicator configured to provide an indication of a level of
charge of the cells of the battery, and wherein the controller is
configured to balance the cells based on the indicated level of
charge of each respective cell.
4. The battery management system of claim 1 wherein in response to
the temperature signal indicating that the temperature is below a
third threshold, the controller is configured to taper the charging
current down as a function of decreasing temperature.
5. The battery management system of claim 4 wherein in response to
the temperature signal indicating that the temperature is below a
fourth threshold, no charging current is supplied to the
battery.
6. The battery management system of claim 1 wherein the tapering of
the current based on temperature is according to a stored
relationship, for example a lookup table, and the controller is
configured to control the charging current based on the stored
relationship.
7. The battery management system of claim 3 wherein the controller
is configured to balance the cells of the battery in a second mode
during charging and a third mode during discharge.
8. The battery management system of claim 3 wherein the controller
is configured to balance the cells in a second mode during charging
in response to the charging current being supplied to the battery
exceeding a selected charging current threshold, for example 0.5
A.
9. The battery management system of claim 3 wherein the controller
is configured to balance the cells in a second mode during charging
in response to a charging voltage being supplied to the battery
exceeding a selected charging voltage threshold, for example
3.0V.
10. The battery management system of claim 3 wherein the controller
is configured to balance the cells in a third mode during discharge
in response to a voltage of a cell of the battery meeting and/or
exceeding a selected voltage threshold.
11. The battery management system of claim 7 wherein the controller
is configured to control a current drawn from each cell during the
third mode during discharge.
12. The battery management system of claim 1 wherein the controller
is configured to control a flow of charging current to the battery
during charging of the battery so that the temperature of the
battery is within a selected range.
13. A battery management system for use in charging a rechargeable
battery, the battery management system comprising: temperature
sensing means for providing a temperature signal based on a
temperature of the rechargeable battery; and control means for
controlling a charging current for charging the rechargeable
battery based on the temperature signal; and balancing cells of the
battery if the charging current supplied to the battery exceeds a
selected charging current threshold.
14. The battery management system of claim 13 wherein in response
to the temperature signal indicating that the temperature exceeds a
first threshold temperature signal value the control means is
configured to taper down the charging current as a function of
increasing temperature; and further configured so that in response
to the temperature signal indicating that the temperature exceeds a
second threshold temperature, no charging current is supplied to
the battery.
15. The battery management system of claim 13 further comprising
charge indicating means for providing an indication of the level of
charge of cells of the battery, and wherein the control means is
configured to balance the cells based on the indicated level of
charge of each respective cell.
Description
FIELD OF THE INVENTION
The present disclosure relates to battery management systems, for
example battery management systems for rechargeable batteries.
BACKGROUND
Rechargeable batteries are commonly used in many technologies, for
example in electric or hybrid vehicles for use both on-highway and
off-highway. For example, rechargeable batteries are frequently
used in automotive applications (on highway), offshore applications
(off highway), in a warehouse environment (for example for use with
mechanical handling equipment such as fork-lift trucks and
autonomous guided vehicles, for example as described in WO
98/49075--off highway) as well as in energy storage applications
(both commercial and domestic--also off highway).
In order to monitor and control the performance of rechargeable
batteries in such applications, a battery management system (BMS)
may be used.
As described in WO 2015/104263, which relates to a storage system
employing the use of battery-powered autonomous guided vehicles, or
robots, there is undesired robot standstill when the batteries are
being charged. This reduces the operational cycle of the storage
system as a whole, for example to typically 16 hours a day to
accommodate 8 hours of charging time. To address this problem, WO
2015/104263 describes a battery comprising a receiving means
enabling releasable connection to a corresponding charge station.
WO 2015/104263 describes interchanging a first battery with a
second battery, so that the robot can remain in use while the first
battery is being charged by a charging station.
SUMMARY OF THE INVENTION
Aspects of the invention are as set out in the independent claims
and optional features are set out in the dependent claims. Aspects
of the invention may be provided in conjunction with each other and
features of one aspect may be applied to other aspects.
DRAWINGS
Embodiments of the disclosure will now be described, by way of
example only, with reference to the accompanying drawings, in
which:
FIG. 1 shows a schematic view of a rechargeable battery pack
comprising an example battery management system;
FIG. 2 shows a schematic view of the cells of a rechargeable
battery in a rechargeable battery pack, such as the one shown in
FIG. 1;
FIG. 3 shows an example electric vehicle comprising a rechargeable
battery pack, such as the one shown in FIG. 1;
FIG. 4 shows another example battery pack;
FIG. 5 shows an example charging point for charging a rechargeable
battery pack, such as the battery pack shown in FIG. 1, comprising
a battery management system; and
FIG. 6 shows an example battery management system for use in
charging a plurality of battery packs, such as the battery pack
shown in FIG. 1.
SPECIFIC DESCRIPTION
Embodiments of the claims relate to a battery management system
(BMS), for example for use in charging a rechargeable battery. As
shown in FIG. 1, a rechargeable battery pack 100 comprises a BMS
101 and a rechargeable battery 105. The BMS 101 comprises a
controller 103 and a temperature sensor 105 that provides a
temperature signal based on the temperature of the rechargeable
battery 103. The rechargeable battery pack 100 can be coupled to a
power source such as a charging station to charge the rechargeable
battery 105 via the BMS 101. The controller 103 of the BMS is
configured to control a charging current provided by the power
source to the rechargeable battery 105 based on the temperature
signal provided by the temperature sensor 107. In response to the
temperature signal indicating that the temperature exceeds a first
threshold temperature signal value, the charging current is tapered
down as a function of increasing temperature.
For example, the rechargeable battery 105 may have a nominal
operating range, such as between 10-40.degree. C. If the
temperature sensor 107 provides a temperature signal indicating
that the temperature of the rechargeable battery 105 reaches a
threshold temperature, for example 42.degree. C., the controller
103 may throttle the current supplied to the rechargeable battery
105 in an effort to stop the temperature of the battery 105 from
continuing to rise. If the temperature signal indicates that the
temperature of the rechargeable battery 105 is higher, for example
43 or 44.degree. C., the controller 103 may throttle the current
further, so that less current is supplied to the battery 105 than
at, for example, 42.degree. C. If the temperature signal indicates
that the temperature of the rechargeable battery 105 is even
higher, so that it reaches a second threshold temperature, for
example 45.degree. C., the controller may throttle the current
altogether so that no current is supplied to the rechargeable
battery 105, in an effort to ensure the temperature of the
rechargeable battery 105 does not exceed the second threshold
temperature and thereby prevent damage being caused to the
rechargeable battery 105.
Because the current supplied to the battery 105 can be controlled
as a function of temperature, the battery 105 can be charged more
quickly without damaging the battery 105. Because the temperature
of the rechargeable battery 105 is used, performance of the battery
105 can be maintained even if the field of application is in
particularly hot or cold environments, such as for vehicles
designed for use in the Antarctic or in the desert.
It will be appreciated from the discussion above that the
embodiments shown in the Figures are merely exemplary, and include
features which may be generalised, removed or replaced as described
herein and as set out in the claims. The actual example actually
shown in FIG. 1 comprises a battery pack 100 comprising a BMS 101
coupled to a rechargeable battery 105. The rechargeable battery
comprises at least one LiFePO.sub.4 cell. The BMS 101 comprises a
controller 103, a current sensor 109, a temperature sensor 107 and
a voltage sensor 111 all coupled in series to the controller
103.
The controller 103, voltage sensor 111 and current sensor 109 in
the example are arranged on a printed circuit board. The
temperature sensor 107 is coupled to the positive end of the stack
of cells. Due to the peltier effect, the positive end of the stack
will become hotter than the negative end in use, and so the
temperature sensor is coupled to the hottest cell of the stack.
The controller 103 further comprises a data store comprising a
stored relationship. In the example shown in FIG. 1, the stored
relationship comprises a lookup table providing set current values
as a function of temperature.
The BMS 101 is couplable to a source of charging current, for
example a charging point 300. The controller 103 is configured to
send a request to the charging point 300 for a charging current to
supply the battery 105. The temperature sensor 107 is configured to
provide a temperature signal based on a temperature of the
rechargeable battery 105. In the example shown in FIG. 1, the
current sensor 109 monitors the charging current to the
rechargeable battery 105 and provides a current signal to the
controller 103. The controller 103 is configured to control (for
example, throttle) the charging current for charging the
rechargeable battery 105 based on the temperature signal. For
example, the controller comprises a current restrictor for
controlling the charging current to the battery 105, for example a
transistor such as a field effect transistor.
In the example shown in FIG. 1, the controller 103 is configured to
control (or throttle) the flow of charging current to the battery
105 during charging of the battery 105. In the example shown in
FIG. 1, the controller 103 is configured to control the charging
current based on the temperature signal and the current signal,
although in other examples the controller 103 may control the
charging current based on just the temperature signal. Tapering of
the current based on temperature is according to the stored
relationship, for example a lookup table, and the controller 103 is
configured to control the charging current based on the stored
relationship.
In operation, the battery pack 100 is coupled to a charging point
300. In response to the controller 103 sending a request to the
charging point 300, charging of the battery 105 begins. The
controller 103 of the BMS 101 of the battery pack 100 may send the
current request in response to making a determination about whether
charging of the battery 105 is required based on at least one
parameter of the battery 105, for example based on the voltage of
the battery 105.
During charging, the temperature sensor 107 monitors the
temperature of the battery 105, and the current sensor 109 monitors
the charging current to the battery 105. The temperature sensor 107
sends a temperature signal to the controller 103 and the current
sensor 109 sends a current signal to the controller 103. In
response to the temperature signal indicating that the temperature
exceeds a first threshold temperature signal value, the controller
103 tapers down (or throttles) the charging current as a function
of increasing temperature. The first threshold temperature may be
42.degree. C. The tapering may be according to a linear
relationship between current and temperature, for example.
In some examples, in response to the temperature signal indicating
that the temperature exceeds a second threshold temperature, the
controller 103 controls or throttles the charging current so that
no charging current is supplied to the battery 105. The second
threshold temperature may be 45.degree. C.
In some examples, in response to the temperature signal indicating
that the temperature is below a third threshold, the controller 103
is configured to taper the charging current down as a function of
decreasing temperature. The third threshold temperature may be
5.degree. C. The tapering may be according to a linear relationship
between current and temperature, for example.
In response to the temperature signal indicating that the
temperature is below a fourth threshold, the controller 103 may be
configured to control or throttle the charging current so that no
charging current is supplied to the battery 105. The fourth
threshold temperature may be 0.degree. C.
The controller 103 may be configured to control the flow of
charging current to the battery 105 during charging of the battery
105 so that the temperature of the battery is within a selected
range. For example, the selected range may have end-points that
correspond to the second and fourth threshold temperatures
described above.
Other embodiments of the claims relate to a BMS, for example the
BMS 101 shown in FIG. 2, that can operate in two modes. In the
first mode a controller 103 controls a charging current for
charging a rechargeable battery 105 based on a temperature signal
received from a temperature sensor 107. The rechargeable battery
105 may comprise a plurality of cells 106, and in the second mode
the controller 103 is configured to balance the cells 106 of the
rechargeable battery 105 based on an indicated level of charge of
each respective cell 106, for example based on a voltage signal
provided by a voltage sensor 111. In this way, a rechargeable
battery 105 comprising a plurality of cells 106 can be rapidly
charged during the first mode, and then once the rechargeable
battery 105 is charged to a certain level, for example a certain
voltage level as indicated by the voltage sensor 111, the BMS 101
can then balance the cells 106 based on their respective levels of
charge, for example so that all of the cells 106 are charged to the
same level.
As noted above, it will be appreciated from the discussion above
that the embodiments shown in the Figures are merely exemplary, and
include features which may be generalised, removed or replaced as
described herein and as set out in the claims. The actual example
actually shown in FIG. 2 shows a battery pack 100 similar to the
battery pack shown in FIG. 1. The battery pack 100 shown in FIG. 2
comprises a BMS 101 coupled to a rechargeable battery 105. The BMS
101 comprises a controller 103, a voltage sensor 111 and a current
sensor 109 arranged in series and coupled to the battery 105, and a
temperature sensor 107 coupled to the battery 105 and the
controller 103.
As shown in FIG. 2, the rechargeable battery 105 comprises three
cells 106 arranged in a stack connected in series. Each cell 106 of
the battery 105 has a corresponding resistor 104 arranged in
parallel with that cell 106. A switch 102 is coupled in series
between each resistor 104 and cell 106.
The controller 103, voltage sensor 111, current sensor 109 and
temperature sensor 106 operate in much the same way as those
described above in relation to FIG. 1. As with the battery pack 100
shown in FIG. 1, the controller 103 is configured to send a request
to a charging point for a charging current to supply the battery
105. The temperature sensor 107 is configured to provide a
temperature signal based on a temperature of the rechargeable
battery 105. The voltage sensor 111 is operable to provide a
voltage signal to act as a charge indicator to provide the
indication of the level of charge of the cells 106 of the battery
105.
The controller is configured to operate in at least two modes. In
the first mode the controller 103 controls a charging current for
charging the battery 105 based on the temperature signal from the
temperature sensor 107, for example in a manner described above in
relation to FIG. 1. In the second mode the controller 103 is
configured to balance the cells 106 of the battery 105 based on the
indicated level of charge of each respective cell 106.
To balance the cells 106 of the battery 105, the controller 103 is
configured to control the charging current to each cell 106 of the
battery 105. To do this, the controller 103 is operable to control
each switch 102 to control the flow of current to each resistor 104
and hence the flow of charging current to each cell 106.
The controller 103 may be configured to balance the cells 106 of
the battery 105 in the first and second modes during charging of
the battery 105 and in a third mode during discharging of the
battery 105. The controller 103 may be configured to control the
current drawn from each cell 106 during the third mode during
discharge.
As with the battery pack 100 of FIG. 1, in operation, the battery
pack 100 is coupled to a charging point. In response to the
controller 103 sending a request to the charging point, charging of
the battery 105 begins. During charging, the temperature sensor 107
monitors the temperature of the battery 105, and sends a
temperature signal to the controller 103. The current sensor 109
monitors the charging current to the battery 105 and sends a
current signal to the controller 103.
In the first mode, in response to the temperature signal indicating
that the temperature exceeds a first threshold temperature, the
controller tapers (or throttles) the charging current down as a
function of increasing temperature.
The BMS 101 operates in the second mode when a selected threshold
is reached. For example, the BMS 101 operates in the second mode
when a selected voltage threshold is reach, as indicated by a
voltage signal provided by the voltage sensor 111. Because the
voltage signal may represent a level of charge of the battery 105,
as described above, the BMS 101 may operate in the second mode once
the level of charge of the battery 105 has reached a certain level.
The voltage threshold may be, for example, 3.1 V, for example, 3.3
V, for example 3.6 V.
In the second mode, the controller 103 balances the cells 106 based
on an indicated level of charge of each respective cell 106, for
example based on the voltage of each respective cell 106. To
balance the cells 106, the controller 103 controls the
corresponding switch 102 for each respective cell 106. By opening
and/or closing each switch 102, the controller 103 controls the
amount of current flowing through each corresponding resistor 104.
Because each resistor 104 is arranged in parallel with each cell
106, controlling the current to each resistor 104 also controls the
current to each cell 106.
The controller 103 may operate in the second mode during charging
in response to the charging current being supplied to the battery
105 exceeding a selected charging current threshold, for example
0.5 A. The controller 103 may operate in the second mode during
charging in response to the charging voltage being supplied to the
battery 105 exceeding a selected charging voltage threshold, for
example 3.0V.
In the second mode, the controller 103 may rank each of the cells
106 of the battery 105 in voltage order, and control the charging
current to each of the cells 106 of the battery 105 based on the
ranking. The controller 103 may also control the charging current
to each of the cells 106 based on an offset between the voltage of
the highest and lowest cells 106. For example, the controller may
control the charging current to each of a selected number of cells
106, for example the top cell 106, the top 2 cells 106, the top 3
cells 106 or the top 4 cells 106, until the offset between each of
those cells 106 with the bottom cell 106 reaches a threshold value,
such as 0.002V.
Once charging is complete, and the battery is used for discharge
(for example by coupling it to a load), the controller 103 may
operate in the third mode. In the third mode, the controller 103
may only balance the cells 106 of the battery 105 during discharge
in response to the voltage of a cell 106 of the battery 105 meeting
and/or exceeding a selected voltage threshold, for example greater
than or equal to 3.6 V, greater than or equal to 3.9 V, greater
than or equal to 4.2 V. By only balancing the cells 106 when their
voltage meets and/or exceeds a selected voltage threshold, cells
106 are only balanced when they have a sufficient level of charge.
The inventors have surprisingly found that balancing the cells 106
when their level of charge is too low is inefficient.
In the first mode, the controller 103 may function in a similar way
to the BMS of FIG. 1. For example, the controller 103 may be
configured to control the flow of charging current to the battery
105 during charging of the battery 105 so that the temperature of
the battery is within a selected range. For example, the selected
range may correspond to the second and fourth threshold
temperatures.
In some examples the battery 105 comprises two stacks of cells 106
arranged in series, and two temperature sensors 107, each
temperature sensor 107 arranged to provide a temperature signal
based on a temperature of each stack of cells 106. The controller
103 may be configured to control the charging current to the
battery 105 based on the respective highest or lowest monitored
temperature of the two temperature sensors 107.
Other embodiments of the claims, for example as shown in FIG. 3,
relate to a BMS 101 for an electric or hybrid vehicle 200 that may
prevent the vehicle 200 from accidentally driving away whilst being
charged. The BMS shown in FIG. 3 comprises a controller 103
configured to communicate with a vehicle drive 201, for example via
an Interface 113. The BMS 101 further comprises a charging
detector, for example a current sensor 109, which detects whether a
rechargeable battery 105 is being charged. The controller 103 is
configured to send a signal to the vehicle drive 201 via the
interface 113 to inhibit operation of the vehicle drive 201 in
response to the charging detector detecting that the rechargeable
battery 105 is being charged.
FIG. 3 shows a vehicle 200 comprising a battery pack 100, such as
the battery pack 100 shown in FIG. 1. The battery pack 100
comprises an interface 113. The battery pack 100 is coupled to a
vehicle drive 201 via the interface 113. The vehicle drive 201 may
be an electric motor, for example.
As noted above, it will be appreciated from the discussion above
that the embodiments shown in the Figures are merely exemplary, and
include features which may be generalised, removed or replaced as
described herein and as set out in the claims. The actual example
actually shown in FIG. 3 shows a battery pack 100 comprising a BMS
101 coupled to the interface 113 and a rechargeable battery 105.
The interface 113 may be a controller area network (CAN) interface.
The BMS 101 comprises a controller 103, a charging detector, which
in the example shown is a current sensor 109, a temperature sensor
107 and a voltage sensor 111 all coupled to the controller 103.
The controller 103 is configured to communicate with the vehicle
drive 201 via the interface 113. The current sensor 109 is
configured to detect whether the battery 105 is being charged.
The controller 103 is configured to send a signal to inhibit
operation of the vehicle drive 201 in response to the current
sensor 109 detecting that the battery 105 is being charged. The
controller 103 may be configured to communicate over a network, for
example a CAN bus. The controller 103 may send the signal to
inhibit operation of the vehicle drive 201 over the CAN bus. For
example, the controller 103 may broadcast a charging advert over
the CAN bus.
As with the battery pack 100 of FIGS. 1 and 2, in operation, the
battery pack 100 is coupled to a charging point. In response to the
controller 103 sending a request to the charging point, charging of
the battery 105 begins. During charging, the current sensor 109
monitors the charging current to the battery 105. The current
sensor 109 sends a current signal to the controller 103. In
response to the controller 103 receiving the current signal, which
indicates that charging current is supplied to the battery 105, the
controller 103 sends a signal to via the interface 113 to inhibit
operation of the vehicle drive 201.
In the example shown in FIG. 3, the BMS 101 comprises an optional
voltage sensor 111 which acts as a charge indicator. The voltage
sensor 111 is configured to provide an indication of the level of
charge of the battery 105 to the controller. For example, the
voltage sensor 111 sends a voltage signal to the controller
103.
In response to the voltage sensor 111 sending a voltage signal to
the controller 103 indicating that the level of charge is below a
charge threshold, the controller 103 is configured to send a
charging advert, for example over a network such as a CAN bus. The
charging advert may be a repeating advert or a single message. It
may be broadcast over a network or sent to specific devices coupled
to the controller 103. Where the charging advert is a repeating
advert, in response to the voltage signal indicating that the level
of charge is above a charge threshold, the controller 103 may no
longer sends a charging advert over the network. The charge
threshold may be, for example, 3.6 V.
In examples where the controller 103 is configured to communicate
over a network, the controller 103 may send a repeating current
request message to a charging point over the network. In response
to the controller 103 receiving a response to the current request
message, the controller 103 may send a signal to inhibit operation
of the vehicle drive 201. The controller 103 may be configured to
repeatedly poll the network for a response to the broadcasted
current request in a time interval following the broadcasted
current request. In response to an instruction received over the
network, the controller 103 may be configured to send a signal to
the vehicle drive 201 overriding the signal to inhibit operation of
the vehicle drive 201. In some examples, the controller 103 is
configured to inhibit operation of the vehicle drive by sending a
repeating charging advert to the vehicle drive 201 over the
network.
Other embodiments of the claims, for example as shown in FIG. 4,
relate to a BMS 101 comprising a controller 103 and a voltage
sensor 111 that can disconnect the charging current to a battery
105 in response to a measured battery voltage exceeding a voltage
threshold. For example, the BMS 101 may be configured to disconnect
the charging current in response to a voltage spike, for example
due to a short-circuit or arcing. In this way, the BMS 101 may act
in a manner similar to a fuse.
As noted above, it will be appreciated from the discussion above
that the embodiments shown in the Figures are merely exemplary, and
include features which may be generalised, removed or replaced as
described herein and as set out in the claims. The actual example
actually shown in FIG. 4 shows a battery pack 100, again similar to
the battery pack of FIG. 1. The battery pack 100 shown in FIG. 4
comprises a rechargeable battery 105 coupled to a BMS 101. The BMS
101 comprises a controller 103 and a voltage sensor 111.
The voltage sensor 111 is configured to measure a voltage of the
battery 105 and send a voltage signal to the controller 103. The
controller 103 is configured to receive a voltage signal from the
voltage sensor 111. The controller 103 is configured to disconnect
a charging current to the battery 105 in response to the voltage
signal (indicative of the measured battery voltage) exceeding a
voltage threshold.
As with the battery pack 100 of FIGS. 1, 2 and 3, in operation, the
battery pack 100 is coupled to a charging point. In response to the
controller 103 sending a request to the charging point, charging of
the battery 105 begins.
The voltage sensor 111 monitors the voltage of the battery 105 at
all times, but in some examples may only monitor the voltage of the
battery 105 during charging of the battery 105. The voltage sensor
111 sends a voltage signal to the controller 103. The controller
103 may control when the voltage sensor 111 is monitoring the
voltage of the battery 105.
In response to the controller 103 receiving a voltage signal
exceeding a voltage threshold, the controller 103 disconnects the
charging current to the battery 105. For example, the BMS 101 may
comprise a field effect transistor, and the controller 103 may
control the field effect transistor to disconnect or throttle the
charging current.
The voltage threshold is selected so that it is larger than a
nominal operating voltage range of the battery 105. For example,
the voltage threshold may be greater than 4 V, greater than 8 V,
greater than 10 V, greater than 15 V, greater than 20 V. The
voltage threshold may be selected to correspond to a voltage spike
caused by arcing, for example due to arcing between charging
contacts on the battery pack 100 and a charging point.
In some examples, the battery 105 comprises a plurality of cells
106. Each cell 106 may comprise a voltage sensor 111 that sends a
respective voltage signal to the controller 103. The controller 103
may be configured to disconnect the charging current to the battery
105 in response to at least one of the voltage signals exceeding
the threshold value.
Other embodiments of the claims, for example as shown in FIG. 5,
relate to a charging point 300 for a rechargeable battery 105 that
can control charging of the battery 105 based on a parameter of the
battery 105, such as temperature or voltage. For example, the
charging point 300 comprises a charging port 305 for electrically
coupling with the rechargeable battery 105 of the rechargeable
battery pack 100. The charging point 300 also comprises a
controller 303, and an interface 313 for receiving at least one
parameter of the rechargeable battery 105. The at least one
parameter may comprise at least one of a temperature of the battery
105, for example as measured using a temperature sensor 107, and a
voltage of the battery 105, for example as measured using a voltage
sensor 111. The controller 303 of the charging point 303 is
configured to control the charging current to the battery 105
during charging of the battery 105 based on the at least one
parameter.
As noted above, it will be appreciated from the discussion above
that the embodiments shown in the Figures are merely exemplary, and
include features which may be generalised, removed or replaced as
described herein and as set out in the claims. The actual example
actually shown in FIG. 5 shows a charging point 300 for charging a
rechargeable battery pack 100, such as the rechargeable battery
pack 100 of FIG. 1, 2 or 4. The charging point 300 shown in FIG. 5
comprises a charging port 305 coupled to a controller 303 via an
interface 313.
As described above in relation to FIGS. 1 and 2, the battery pack
100 comprises a BMS 101 coupled to a rechargeable battery 105. The
BMS 101 comprises a controller 103, an optional current sensor 109,
a temperature sensor 107 and a voltage sensor 111 all coupled to
the controller 103. In some examples the BMS 101 may comprise only
one of, or any combination of, the current sensor 109, the
temperature sensor 107 and the voltage sensor 111.
The controller 103 of the battery pack 100 is configured to send a
request to the charging point 300 for a charging current to supply
the battery 105. The temperature sensor 107 is configured to
provide a temperature signal based on a temperature of the
rechargeable battery 105. The current sensor 109 monitors the
charging current to the rechargeable battery 105 and is configured
to provide a current signal to the controller 103. The voltage
sensor 111 monitors the voltage of the rechargeable battery 105 and
is configured to provide a voltage signal to the controller
103.
The charging port 305 is configured to electrically couple with the
rechargeable battery 105 of the rechargeable battery pack 100. The
controller 303 is configured to receive at least one parameter of
the rechargeable battery 105 of the battery pack 100 via the
interface 313. The at least one parameter comprises at least one of
a temperature of the battery received as a temperature signal from
the temperature sensor 107 and a voltage of the battery 105
received as a voltage signal from the voltage sensor 111, via the
controller 103 of the BMS 101.
The controller 303 of the charging point 300 is configured to
control the charging current to the battery 105 during charging of
the battery 105 based on the at least one parameter.
The controller 303 is configured to communicate over a network, for
example a CAN bus, via the interface 313 with the controller 103 of
the BMS 101 of the battery pack 100. The controller 303 is
configured to communicate with a rechargeable battery pack 100 via
the interface 313 and the charging port 305. The controller 303 is
configured to control the charging current to the battery 105 based
on the at least one other parameter being received in a message
over the network.
In use, the rechargeable battery pack 100 is coupled to the
charging point 300 via the charging port 305. Charging can begin in
a number of different ways. For example, the controller 103 of the
BMS 101 of the battery pack 100 may send a current request to the
charging point 300. In response to receiving the current request,
the controller 303 of the charging point 300 may begin charging the
battery 105 of the battery pack 100. The controller 103 of the BMS
101 of the battery pack 100 may send the current request in
response to making a determination about whether charging of the
battery 105 is required based on the at least one parameter.
In other examples, the controller 303 may send a signal or message
to the controller 103 of the BMS 101 of the battery pack 100,
requesting information regarding the at least one other parameter.
In response, the controller 103 of the BMS 101 of the battery pack
100 may send a signal or message comprising information relating to
the at least one parameter to the controller 303 of the charging
point 300. In response to receiving this information, the
controller 303 of the charging point 300 may make a determination
about whether to start charging of the battery 105 of the battery
pack 100.
Once charging begins, the controller 303 of the charging point 300
controls the charging current to the battery 105 during charging of
the battery 105 based on the at least one parameter. For example,
in response to a voltage signal indicating that the level of charge
of the battery 105 has reached a charge threshold, the controller
303 may taper or cut off the charging current supplied to the
battery 105. As described in relation to FIG. 3, the charge
threshold may be, for example, 3.6 V.
As described above in relation to FIGS. 1 and 2, the controller 103
may be configured to control (or throttle) the charging current for
charging the rechargeable battery 105 based on the temperature
signal. For example, the controller comprises a current restrictor
for controlling the charging current to the battery 105, for
example a field effect transistor.
The at least one parameter may comprise an instruction to send
current. For example, the charging point 300 may be configured to
commence the charging current to the battery 105 and therefore
start charging upon receiving a first message via the interface
313, and to inhibit the charging current to the battery 105, and
therefore stop charging, upon receiving a second message via the
interface 313.
The controller 303 of the charging point 300 may be configured to
repeatedly send an advertisement message via the interface 313. The
charging point 300 may be configured to control the charging
current to the battery 105 upon acknowledgement of receipt of the
advertisement message.
In the example described above, the controller 303 of the charging
point 300 is configured to communicate with a rechargeable battery
pack 100 via the interface 313 and the charging port 305. In other
examples the controller 303 of the charging point 300 is configured
to communicate with a rechargeable battery pack 100 via the
interface 313 but not via the charging port 305. For example, the
charging point 300 may be configured to communicate with a
rechargeable battery pack 100 via a network port, such as a CAN
port that is operable to couple with the rechargeable battery pack
100.
Other embodiments of the claims, for example as shown in FIG. 6,
relate to a BMS 101 that can be used in charging a plurality of
rechargeable battery packs 100, for example so that the battery
packs 100 are charged to the same level. Each battery pack 100
comprises a rechargeable battery 105 and a BMS 101 comprising a
controller 103. Each of the battery packs 100 are coupled to a
charging point 300, either in series or in parallel. The controller
103 of one battery pack 100 is configured to communicate with the
controller 103 of another battery pack 100, and upon communicating
with each other each battery pack 100 is configured to designate
itself as either a "master" or "slave". The controller 103 of the
master battery pack 100 is configured to receive information
regarding parameters regarding the battery 105 of the slave battery
pack 100 and control a charging current from the charging point 300
to the batteries 105, of either the slave or both the master and
the slave battery packs 100, based on the information received from
the slave battery pack 100.
As noted above, it will be appreciated from the discussion above
that the embodiments shown in the Figures are merely exemplary, and
include features which may be generalised, removed or replaced as
described herein and as set out in the claims. The actual example
actually shown in FIG. 6 shows an example BMS 101a for charging a
plurality of batteries 105a, 105b.
FIG. 6 shows two battery packs 100a and 100b. The two battery packs
100a, 100b shown in FIG. 6 are coupled to each other and to a
charging point 300, for example the charging point of FIG. 5
described above.
The first battery pack 100a comprises a BMS 101a coupled to a
rechargeable battery 105a. The BMS 101a comprises a controller
103a. The second battery pack 100b also comprises a BMS 101b
coupled to a rechargeable battery 105b. The BMS 101b also comprises
a controller 103b.
The controller 103a of the first BMS 101a is configured to
communicate with the controller 103b of the second BMS 101b, for
example via an optional interface (not shown). Upon communication
with the second BMS 101b, the controller 103a of the first BMS 101a
is configured to designate itself as a master controller 103a and
designate the other controller as a slave controller 103b.
The master controller 103a is configured to receive information
regarding parameters of the second battery 105b of the plurality of
batteries from the slave controller 103b. The parameters of the
battery 105 may include at least one of: pack temperature, pack
voltage, charging current flow to pack, number of cells per pack,
charging current flow to each cell and voltage of each cell.
The master controller 103a is configured to control a charging
current received from the barging point 300 to the plurality of
batteries 105a, 105b based on the received information and based on
information regarding parameters of the first battery 105a.
As with the battery pack 100 of FIGS. 1 and 2, in operation, the
battery packs 100a, 100b are coupled to the charging point 300. The
master controller 103a may make a determination when the plurality
of batteries 105a, 105b need charging based on the received
information regarding the first battery 105a, the second battery
105b or a combination of both.
In response to the master controller 103a sending a request to the
charging point, charging of the batteries 105a, 105b begins. The
master controller 103a controls the current supplied to both
batteries 105a, 105b based on the received information. For
example, the master controller 103a may control current supplied to
the batteries 105a, 105b based on the highest or lowest temperature
of the plurality of batteries.
The master controller 103a may control the current supplied to the
batteries 105a, 105b in a number of different ways. For example, in
some examples the master controller 103a may directly control the
flow of current from the charging point 300 to the second battery
pack 100b. In other examples, the master controller 103a may be
configured to send instructions to the slave controller 103b. The
master controller 103a may send a signal to the slave controller
103b telling the slave controller 103b what current to request from
the charging point 300.
The master controller 103a may control the current supplied to the
batteries 105a, 105b so that both batteries 105a, 105b are charged
to the same level. This may be useful when one battery charges more
quickly than the other. For example, the master controller 103a may
be configured to supply current to both batteries 105a, 105b at an
equal rate until one of the batteries 105a, 105b reaches a
threshold value, such as a selected voltage threshold such as 3.1
V, 3.3 V, 3.6 V. Once one of the batteries reaches the selected
voltage threshold, the master controller 103a may be configured to
supply current only to the other battery until both batteries are
at the same voltage level (for example so that both batteries are
charged to the same level).
It will be understood in the context of the present disclosure that
the BMS 101 or battery pack 100 described above in relation to a
particular Figure may comprise features that may be used in the
context of another example.
For example, the battery pack 100 of any of FIGS. 2, 3, 4, 5 and 6
may be configured to control charging of the battery 105 based on a
temperature of the battery 105, for example as described above in
relation to FIG. 1. For example, the BMS 101 of the battery pack
100 may comprise a current sensor 109 and a temperature sensor 107
coupled to the controller 103. The temperature sensor 107 may be
configured to provide a temperature signal based on a temperature
of the rechargeable battery 105, and the current sensor monitors
the charging current to the rechargeable battery 105 and provides a
current signal to the controller 103. The controller 103 may be
configured to control the charging current based on the temperature
signal and the current signal.
The battery pack 100 of any of FIGS. 1, 3, 4, 5 and 6 may be
configured to operate in two modes, as described above in relation
to FIG. 2. For example, the BMS 101 of the battery pack 100
comprises a controller 103, a voltage sensor 111 and a current
sensor 109 arranged in series and coupled to the battery 105, and a
temperature sensor 107 coupled to the battery 105 and the
controller 103. The temperature sensor 107 may be configured to
provide a temperature signal based on a temperature of the
rechargeable battery 105. The voltage sensor 111 may be operable to
provide a voltage signal to act as a charge indicator to provide
the indication of the level of charge of the cells 106 of the
battery 105. The controller 103 may be configured to operate in at
least two modes. In the first mode the controller 103 controls a
charging current for charging the battery 105 based on the
temperature signal from the temperature sensor 107, for example in
a manner described above in relation to FIG. 1. In the second mode
the controller 103 is configured to balance the cells 106 of the
battery 105 based on the indicated level of charge of each
respective cell 106.
The battery pack 100 of any of FIGS. 1, 2, 4, 5 and 6 may be
configured to communicate with a vehicle drive 201 as described
above in relation to FIG. 1. For example, the battery pack 100
comprises an interface 113. The battery pack 100 is coupled to a
vehicle drive 201 via the interface 113. The controller 103 may be
configured to communicate with the vehicle drive 201 via the
interface 113. The current sensor 109 may be configured to detect
whether the battery 105 is being charged. The controller 103 may be
configured to send a signal to inhibit operation of the vehicle
drive 201 in response to the current sensor 109 detecting that the
battery 105 is being charged.
The battery pack 100 of any of FIGS. 1, 2, 3, 5 and 6 may be
configured to disconnect a charging current to the battery 105 in
response to a measured battery voltage exceeding a voltage
threshold. For example, the BMS 101 of the battery pack 100
comprises a controller 103 and a voltage sensor 111. The voltage
sensor 111 may be configured to measure a voltage of the battery
105 and send a voltage signal to the controller 103. The controller
103 may be configured to disconnect a charging current to the
battery 105 in response to the voltage signal exceeding a voltage
threshold.
The battery pack 100 of any of FIGS. 1, 2, 3, 4 and 6 may be
configured to operate with a charging point 300 as described above
in relation to FIG. 5. For example, the BMS 101 of the battery pack
100 may comprise at least one of, or any combination of, a current
sensor 109, a temperature sensor 107 and a voltage sensor 111,
arranged to provide information regarding at least one parameter of
the battery 105 to a controller 303 of a charging point 300. For
example, the temperature sensor 107 may be configured to provide a
temperature signal based on a temperature of the rechargeable
battery 105. The current sensor 109 may be configured to provide a
current signal to the controller 103. The voltage sensor 111 may be
configured to provide a voltage signal to the controller 103. The
battery pack 100 may be adapted to couple with a charging port 305
of a charging point 300. The charging point 300 may comprise a
controller 303 coupled to charging port 305 via an interface 313
and configured to control the charging current to the battery 105
during charging of the battery 105 based on the at least one
parameter.
In the context of FIG. 6, each battery pack 100a, 100b may comprise
the features of the battery packs 100 shown in FIGS. 1, 2 and 3.
For example, each BMS 101a, 101b may comprise a current sensor 109,
a voltage sensor 111 and/or a temperature sensor 107. The
controllers 103a, 103b, or the master controller 103a, may be
configured to control the charging current to each of the batteries
105a, 105b based on signals received from these sensors, as
described above in relation to FIGS. 1 and 2. Each battery pack
100a, 100b may also comprise an interface 113 and each controller
103a, 103b, or the master controller 103a, may be configured to
control a vehicle drive 201, as described above in relation to FIG.
3.
In some examples, the BMS 101 does not have a voltage sensor 111 or
a current sensor 109. In some examples the BMS 101 does not
comprise a data store.
Each battery 105 may comprise a plurality of cells 106, as
described above in relation to FIG. 2. Each cell 106 may have a
corresponding resistor 104 and switch 102 for controlling the
current to each cell 106. In some examples, the battery 105
comprises two stacks of cells 106, for example two stacks of three
cells 106. The BMS 101 may have two temperatures sensors 107, each
temperature sensor 107 arranged to provide a temperature signal
based on a temperature of a respective stack of cells 106. In such
examples, the controller 103 may be configured to control the
charging current to the battery 105 (for example to each stack
and/or individual cell 106) based on the respective highest or
lowest monitored temperature of the two temperature sensors
107.
In some examples, the controller 103 of the BMS 101 comprises a
plurality of inputs or channels for receiving a plurality of input
signals from the battery 105. The controller 103 may be configured
to determine the number of cells 106 based on the input signals.
For example, the controller 103 may comprise 15 channels. For
example, the BMS 101 may be configured to determine the number of
cells 106 based on a voltage measurement from each cell 106. The
controller 103 may be configured to balance the cells 106 based on
the determined number of cells 106.
The controller 103 may comprise an interface 113, 313 for
communicating over a network, such as a CAN bus or a serial bus
such as an RS485 bus, for example the CAN bus as described in
relation to FIG. 3 or FIG. 5. The controller 103 may be configured
to communicate information regarding charging and discharging of
the battery 105 over the network. The controller 103 may be
configured to communicate information regarding charging and
discharging of the battery 105 to a charging station 300 over a
network.
The controller 103 may be configured to communicate at least one
of: temperature of battery, indication of level of charge of
battery, charging current to battery and voltage of battery over
the network.
The controller 103 may be configured to control charge or discharge
of the battery 105 based on instructions received over the network.
For example, in response to an instruction received over the
network indicating a request to stop charging, the controller 103
may be configured to reduce the charging current to the battery 105
until the charging current is below a selected charging current
threshold value, and in response transmit a message over the
network indicating that the charging of the battery 105 has ended.
The selected charging current threshold may, in some examples,
correspond to no charging current to the battery 105.
The controller 103 may be configured to control a temperature
control system to heat or cool the battery 105 based on the
temperature signal. The controller 103 may be configured to
activate the temperature control system to cool the battery 105 in
response to the temperature exceeding a first threshold
temperature, for example the first threshold temperature described
above in relation to FIG. 1. The controller 103 may be configured
to activate the temperature control system to heat the battery 105
in response to the temperature falling below a third threshold
temperature, for example the third threshold temperature described
above in relation to FIG. 1.
Although LiFePO.sub.4 (lithium iron phosphate) cells have been
described above, any lithium cell chemistry may be used, such as
LiCoO.sub.2 or LiMn.sub.2O.sub.4, lithium titanate, lithium suphur,
lithium polymer or lithium-ion polymer. Other cell chemistries may
also be used.
Other embodiments of the disclosure may relate to a BMS for use in
charging and/or discharging a rechargeable battery. The BMS may be
the BMS 101 described above. The BMS 101 comprises a controller 103
and two temperature sensors: (i) a first temperature sensor 107 for
measuring the temperature of at least one battery cell 106 of the
rechargeable battery 105, and (ii) a second temperature sensor for
measuring the temperature of elements of the BMS. The controller
103 is configured to control a charging current for charging the
rechargeable battery 105 based on a temperature signal from the
first temperature sensor 107, and stop the flow of current to
and/or from the rechargeable battery 105 in response to the second
temperature sensor indicating that the temperature of elements of
the BMS 101 exceed a threshold temperature.
For example, the controller 103 is configured to stop the flow of
charging current to the rechargeable battery 105 in response to the
second temperature sensor indicating that the temperature of
elements of the BMS 101 exceed a threshold temperature.
Additionally or alternatively, the controller 103 is configured to
stop the flow of discharge current from the rechargeable battery
105 in response to the second temperature sensor indicating that
the temperature of elements of the BMS 101 exceed a threshold
temperature. Stopping the flow of charge or discharge current may
comprise stopping the flow of current completely so that no current
at all flows to and/or from the rechargeable battery 105.
It will be understood that the BMS may comprise any of the
functionality of the BMS 101 described above. For example, the
controller 103 of the BMS 101 may be configured so that in response
to the temperature signal from the first temperature sensor 107
indicating that the temperature exceeds a first threshold
temperature signal value, the charging current is tapered down as a
function of increasing temperature.
The elements of the BMS 101 may comprise at least one voltage
controlled impedance operable by the controller 103 for controlling
the charging current supplied to and/or from the rechargeable
battery 105. The voltage controlled impedances may comprise
transistors such as insulated gate bipolar transistors, IGBTs,
field effect transistors, FETs, such as junction field effect
transistors, JFETS, insulated gate field effect transistors,
IGFETS, metal oxide semiconductor field effect transistors,
MOSFETs, and any other type of transistor.
In response to the controller 103 stopping the flow of charging
and/or discharging current to and/or from the rechargeable battery
105 in response to the threshold temperature for the second
temperature sensor being reached, the controller 103 may be
configured to wait a set period of time before allowing the flow of
current again. Additionally or alternatively, the controller 103
may be configured to wait until the second temperature sensor
indicates that elements of the BMS 101 are at a temperature value
lower than the threshold temperature, for example 20 degrees
centigrade below the threshold temperature. For example, the
controller 103 may be configured to allow the flow of current to
resume when the second temperature sensor indicates that elements
of the BMS 101 are below a second threshold temperature for the
second temperature sensor.
The second temperature sensor may therefore have a first threshold
temperature and a second threshold temperature. The first threshold
temperature for the second temperature sensor may be one that, if
reached, stops the flow of current to and/or from the rechargeable
battery 105, and the second threshold temperature for the second
temperature sensor may be one that, if reached, allows the flow of
current to and/or from the rechargeable battery 105 to resume. The
first threshold temperature for the second temperature sensor may
be greater than the second threshold temperature for the second
temperature sensor. For example, the first threshold temperature
for the second temperature sensor may be 110 degrees centigrade.
The second threshold temperature for the second temperature sensor
may be 90 degrees centigrade.
The first and optionally second threshold temperatures for the
second temperature sensor may be greater than a threshold
temperature for the first temperature sensor 107. In other words,
the threshold temperatures for elements of the BMS 101 may be
greater than the threshold temperatures for the rechargeable
battery 105. The rechargeable battery 105, and in particular the
cells 106 of the rechargeable battery 105, may have a greater heat
capacity than elements of the BMS 101 and may act as a heat sink
for elements of the BMS 101. Providing threshold temperatures for
elements of the BMS 101 that are greater than threshold
temperatures for the rechargeable battery 105 may allow the
controller 103 to provide a safety cut-out feature and prevent the
BMS 101 and/or the battery 105 from getting too hot.
The first and optionally second threshold temperatures for the
second temperature sensor may therefore be a fifth and optionally
sixth threshold temperature signal value for the controller 103.
The fifth and optionally sixth threshold temperature signal values
may be greater than any of the first, second, third or fourth
threshold temperature signal values for the first temperature
sensor 107. In some examples, the BMS 101 may comprise an interface
103, for example operable to communicate over a CAN. Any of the
threshold temperatures may be configurable via the interface 103,
for example the threshold temperatures may be configurable via a
CAN.
All the embodiments described above, and each and every claimed
feature may be used in on-highway and/or off-highway applications.
For example, the embodiments described above, and each and every
claimed feature may be used solely in on-highway or off-highway
applications. The embodiments described above and each and every
claimed feature may be used in an on-highway or an off-highway
electric machine, or an on-highway or an off-highway electric
apparatus. For example the embodiments described above and each and
every claimed feature may be used in electric or hybrid vehicles
for use on-highway and/or off-highway. For example, the
rechargeable battery packs 100 described herein may be used, for
example in electric or hybrid vehicles for use on-highway and/or
off-highway. For example, embodiments described above and each and
every claimed feature may be used in automotive applications (on
highway), offshore applications (off highway), in a warehouse
environment (for example for use with mechanical handling equipment
such as fork-lift trucks and autonomous guided vehicles, for
example as described in WO 98/49075--off highway) as well as in
energy storage applications (both commercial and domestic--also off
highway).
In some examples, one or more memory elements can store data and/or
program instructions used to implement the operations described
herein. Embodiments of the disclosure provide tangible,
non-transitory storage media comprising program instructions
operable to program a processor to perform any one or more of the
methods described and/or claimed herein and/or to provide data
processing apparatus as described and/or claimed herein.
The methods and apparatus outlined herein may be implemented using
controllers and/or processors which may be provided by fixed logic
such as assemblies of logic gates or programmable logic such as
software and/or computer program instructions executed by a
processor. Other kinds of programmable logic include programmable
processors, programmable digital logic (e.g., a field programmable
gate array (FPGA), an erasable programmable read only memory
(EPROM), an electrically erasable programmable read only memory
(EEPROM)), an application specific integrated circuit, ASIC, or any
other kind of digital logic, software, code, electronic
instructions, flash memory, optical disks, CD-ROMs, DVD ROMs,
magnetic or optical cards, other types of machine-readable mediums
suitable for storing electronic instructions, or any suitable
combination thereof.
Embodiments of the disclosure provide computer program products,
and computer readable media, such as tangible non-transitory media,
storing instructions to program a processor to perform any one or
more of the methods described herein. Other variations and
modifications of the apparatus will be apparent to persons of skill
in the art in the context of the present disclosure.
With reference to the drawings in general, it will be appreciated
that schematic functional block diagrams are used to indicate
functionality of systems and apparatus described herein. It will be
appreciated however that the functionality need not be divided in
this way, and should not be taken to imply any particular structure
of hardware other than that described and claimed below. The
function of one or more of the elements shown in the drawings may
be further subdivided, and/or distributed throughout apparatus of
the disclosure. In some embodiments the function of one or more
elements shown in the drawings may be integrated into a single
functional unit.
It is suggested that any feature of any one of the examples
disclosed herein may be combined with any selected features of any
of the other examples described herein. For example, features of
methods may be implemented in suitably configured hardware, and the
configuration of the specific hardware described herein may be
employed in methods implemented using other hardware.
* * * * *